Department of Orthopaedic Surgery, University of Southern California Keck School of Medicine, 1520 San Pablo St., Suite 2000, Los Angeles, CA, 90033, USA.
Department of Radiology, Loma Linda University Medical Center, Loma Linda, CA, USA.
Arch Orthop Trauma Surg. 2024 Apr;144(4):1503-1509. doi: 10.1007/s00402-024-05210-y. Epub 2024 Feb 14.
The use of magnetic resonance imaging (MRI) with a magnetic intramedullary lengthening nail in place is contraindicated per the manufacturer due to the concern of implant activation and migration. A prior in vitro study did not confirm these complications only noting that a 3.0 T MRI weakened the internal magnet. Therefore, a retrospective analysis of patients who underwent an MRI with a magnetic nail in place was performed to determine if any adverse effects occurred in the clinical setting.
A retrospective review of all patients who underwent an MRI with a magnetic lengthening nail in place was performed. The time spent being imaged in the MRI, number of times the patient entered the MRI suite, and the images obtained were recorded. Radiographs were performed before and after the MRI to determine if any hardware complications occurred. The patients were monitored for any adverse symptoms while they were in the suite.
A total of 12 patients with 13 nails were identified. Two patients underwent imaging with a 3.0 T MRI while the remaining 10 underwent imaging with a 1.5 T MRI. Each patient entered the MRI suite 2.1 times and spent an average of 84.7 min being imaged in the MRI (range 21-494). No patients noted any adverse symptoms related to the nail while in the suite and no hardware complications were identified.
MRI appears to be safe with a magnetic nail in place and did not result in any complications. Given the manufacturer's recommendations, informed consent should be obtained prior to an MRI being performed and a 3.0 T MRI should be avoided when possible if further activation of the nail is required.
由于担心植入物激活和迁移，制造商禁止在有内置髓内延长钉的情况下使用磁共振成像（MRI）。先前的一项体外研究并未证实这些并发症，仅指出 3.0T MRI 会削弱内置磁铁的磁力。因此，对接受 MRI 检查且内置磁钉的患者进行了回顾性分析，以确定在临床环境中是否发生任何不良影响。
对所有接受内置磁钉 MRI 检查的患者进行了回顾性分析。记录了在 MRI 中的成像时间、患者进入 MRI 套房的次数以及获得的图像。在 MRI 前后拍摄 X 光片，以确定是否发生任何硬件并发症。监测患者在套房中是否有任何不良症状。
共确定了 12 例患者的 13 枚钉。2 例患者进行了 3.0T MRI 成像，其余 10 例患者进行了 1.5T MRI 成像。每位患者进入 MRI 套房 2.1 次，平均在 MRI 中成像 84.7 分钟（范围 21-494 分钟）。没有患者在套房中出现与钉子相关的任何不良症状，也未发现任何硬件并发症。
MRI 似乎在有内置磁钉的情况下是安全的，不会导致任何并发症。鉴于制造商的建议，在进行 MRI 检查之前应获得知情同意，如果需要进一步激活钉子，应尽可能避免使用 3.0T MRI。
